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accessing data in a QFile

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nass

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Posts: 57

Location: Greece

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Thursday, September 21st 2006, 1:19pm

accessing data in a QFile

hello everyone,
i have been ssaving some variable values in a file using QFile and QDataStream.
the variables are of types Q_UINT8, Q_INT8, Q_UINT32, Q_INT32, float, double and even QString...
write and read operation work wonderfully so far..

but now i need to be able to access certain variables down the stream..
so if i have written the stream in the file as:

QDataStream ds(&aQFile)
ds<<aUINT8<<aUINT32<<aINT8<<aFloat<<aDouble<<aQString<<anotherINT8..... etcetc

and now i want to access directly aINT8, how do i do it?
i read in te documentation at the QFile::at(Offset off) function... i guess the offset is just an integer number of the counted bytes till the beginning of the variable i want to read..
however i wonder how im gonna compute the offsets..
mean in the above case its easy to find the offset of aINT8.. it is 5 (bytes) ... or not?
however how can i get the offset of anotherINT8 ?
thank you for your help
nass

AP.Sakkthivel

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Friday, September 22nd 2006, 4:45am

I am not sure about your qt version..

In qt 4, QDataStream has an api to locate a particular byte.

No worry...refer QDataStream class well
Regards
- $akthi

You never know, how soon it may be too late…